Soaking pit curb wall with fixed elevation



Jan. 12, 1954 c. L. HERMAN SOAKING PIT CURB WALL W ITH FIXED ELEVATION 3Sheefs-Sheet 1 Filed April 50, 1953 N 4 W 2 A a a.

Jan. 12, 1954 c. L. HERMAN 2,665,895

SOAKING PIT CURB WALL WITH FIXED ELEVATION Filed April 50, 1953 3Sheets-Sheet 2 IN VEN TOR.

///5 ATTORIVZ-V Jan. 12, 1954 c. HERMAN 2,665,895

SOAKING PIT CURB WALL WITH FIXED ELEVATION Filed April 50, 1953 5Sheets-Sheet 3 INVEN TOR.

Patented Jan. 12, 1954 SOAKING PIT CURB WALL WITH FIXED ELEVATION CarlL. Herman, Canonsburg, Pa., assignor to Amsler Morton Corporation,Pittsburgh, Pa., a

corporation of Delaware Application April 30, 1953, Serial No. 352,229

11 Claims. 1

This invention relates generally to soaking pits or other furnacessimilarly constructed with a large furnace chamber opening, and moreparticularly to the curbing or perimeter surrounding the furnace chamberopening which must be of fixed elevation or position. Yet, the walls ofthe furnace chamber must be permitted to expand or contract withoutlosing the seal between the closure and the opening.

The problem of maintaining the seal around a large furnace opening, suchas a pit furnace is difficult. The masonry, forming the furnace chamber,must expand and contract considerably more than that of the frameworkthat holds the curbing, supports cover carriages if any, and alsosupports the seal that extends completely around the furnace opening.The way these problems have been coped with heretofore is to constructthe furnace so that the whole of the structure may; expand and contractuniformly. A small leak in the seal would not be too bothersome but whenthe furnace pressures show a large differential, then a leak in the sealis troublesome.

The vast difference in the expansion and contraction of the outermaterials and the furnace chamber linings causes the seal to beinterrupted, and the furnace to distort to such a degree that the. coveror door will not fit properly, which results in a leakage of the heatand gases or a leakage of air into the furnace chamber depending uponthe pressure conditions in the furnace. Such a furnace structure cannotbe depended upon for good operation over a considerable period of time.The curbing twists and gives trouble with the track supported carriagefor lifting and moving the covers from the furnace chamber openings suchas a soaking pit.

The principal object of this invention is the provision of a curbing orperimetral margin surrounding a large furnace opening that is fixedrelative to the foundation of the structure while permitting the furnacewalls to expand and contract without a'ffecting the curbing or the .sealof the furnace opening supported by this perimetral margin.

This curbing or perimetral opening of a fur-.

nace chamber has a fixed elevation or location and permits the seal tobe maintained regardless of the temperature or temperature changes inthe furnace chamber. This is accomplished by supporting the curbing fromthe outer wall structure which is made of fabricated steel. The

curbing then ties in with the furnace Wall struc-- ture by providing aseries of stepped spaces that are independently shut off from each otherwhen expanded and which permit the ready movement of the furnace wall orcurbing structure without completely closing the stepped spaces in whichhot air or gases are entrapped. The curbing masonry material, beingrelatively small as compared to that of the furnace walls, will notexpand or contract to such a degree as to disturb the seal or the trackwhich supports the cover carriage.

The curbing is then supported to a degree and actually insulated fromthe furnace walls which provides improved furnace structure in that thecurbing does not get overheated or destroyed, and the walls of thefurnace chamber may be readily replaced without disturbing the curbing.The walls have all the freedom of expansion or contraction withoutinterrupting the seal or in otherwise changing the curbing.

Where a center wall is employed between two furnace chambers, thecurbing may be hung from a bridge member, and thus be independent fromthe wall but still be sealed therewith and carry two sealing troughs forindependent covers.

This invention is better illustrated on a pit furnace as it presentsmore problems in that the furnace opening is upward, and the cover mustbe removed by a carriage supported by the rails carried on the samestructure supporting the curbing.

Other objects and advantages appear hereinafter in the followingdescription and claims:

The accompanying drawing shows for the purpose of 'exemplificationwithout limiting-the invention or claims thereto certain practical em-'bodiments of the invention wherein:

Fig. 1 is a view in vertical section of a side wall of a soaking pitfurnace with the carriage removed.

Fig. 2-is a view in horizontal section taken on the lines 2-2 of Fig. 1.

Fig. 3 is a view in vertical section of an end wall of a soaking pitfurnace showing a cover in place. I

Fig. 4 is aview in vertical section of a common wall between adjacentsoaking pit furnace chambers.

Fig. 5 is a view in horizontal section taken on the line55 of Fig. 4.

Referring to Fig. 1 the furnace soaking pit is provided with a furnacechamber I with a curb 2 formed by the wall as illustrated in Fig. 2, theliner of which is thin in its intermediate portion and heavier at theends as indicated at 3. This wall also tapers upwardly to the curbingasindicated at 4. r e v H The'furnaee wall structure is lined with afire stone or silica brick 5. This is backed up by a back-up wall 6 offire brick of secondary quality, which is covered with an insulation asindicated at i that may be a diatomaceous earth with asbestos fiberbinder. This insulation is then enclosed by a steel shell or wall 8.

The steel wall 8 is braced with vertical stanchions and is a structuralsupport for the furnace. This wall has secured thereto the seat or shelfmember Ill which extends around the pit and is supported at intermediatesections. by the triangular brace plates II that are welded tatheunderside of the shelf in and to the wall 8. The insulating section 1extends up to the underside of the shelf in and above the wall 6.

The tops of the inner lining 5 and the back-up wall 6 are formed insteps such as. indicated at 1.2,. i 3, I4, l5, and 16, the latter beingexposed to. the. chamber of the pit. These steps sometimes vary in widthand height depending upon the character of the curbing to beconstructed. However, they provide pockets or air spaces which afterbeing heated become isolated from one another and form expansion spacesbetween these wall sections and the curb structure.

The steel wall 8 extends clear to the top of the furnace as shown andsupports the curbing. A small section of insulating material (I isprovided along the inner face of the steel wall 8 and against which theends of the special shapes of super duty fire clay blocks are mounted onthe curbing. These blocks form the curbing and the lowermost block isthe smallest block and the uppermost block is the largest block. Asillustrated' in Fig. 1, the blocks numbered l8, I9, 20, M, 22, and 23,and each block asillustrated in Fig. 2, is provided with a vertical slot24 on its outer face for receiving one half of the head of the wall-tiemember 25, the other half being received in a similar vertical groove 24of the adjacent block.

The wall-tie members 25, as shown in Fig. 6 are short T-headed sectionsthat are provided with a bolt section 26 formed integral therewith andwhich extend through the slot 21 formed by the spaced angle plate 28secured to the outer surface of the steel wall 8. Washers 30 are placedunder the nuts ill for securing the short T-headed wall ties against theouter edges of the angle plates 28 for supporting the ends of thestepped curbed blocks 8 to 23 inclusive to the outer steel structure.Each T-headed wall-tie member is engaged in the slots 24 of sub-j acentblocks as well as laterally adjacent blocks as indicated in Fig. 1.

Since the lowermost block is resting upon the seat of the shelf inandthe other blocks are resting upon each immediate sub-jacent block inturn, the position of the inner ends of the blocks is fixed relative tothe curb line and the pit. The blocks '20 and 2! are of the same lengthwhich provides a deeper vertical seal between the steps l4 and 15.However, the steps i246 are air steps and thus become sealed off andindependent from one another upon expansion of the refractory wall belowthe blocks Hi to 23, causing the latter t0 engage the vertical Wallformed by the steps l2-l6.

The opening above the step I6 is filled with Gunite after expansion hastaken place in the burning of the furnace walls. However, the walls mayexpand and contract vertically and without disturbing the curbs owing tothe fact that the walls can breathe and move in the air spacesformedabove the steps I! to 6 inclusive. The

4 caulking material in the space above the step [6 may be such that itis soft and will withstand the breathing of the furnace wall below thecurb line.

The curb masonry 2 is made of span-resistant refractory shapes and itis. supported on. the uppermost special shaped super duty fire; clayblock numbered I8 to 23. This curb brick is capable of withstanding2,600 F. and is dished to receive the trough 32 made of an alloy steelfor the purpose of receiving silica sand that is employed to receive andseal the depending seal flange on the cover that closes over the pitopening.

The steel wall 8 is also provided with a stiffener, angle 33 which issecured to the outer face of the steel wall 8 adjacent the lower end ofthe triangular gusset plates 1 I and aids in carrying the fabricatedstructural beam member 311 made of two spaced channel members with anintermediate H-beam therebetween which further stiffens the wall. Thisstructural beam member is referred to as the rail girder and supportsthe channel members 35 that extend transversely 'of the girder 34. Thesechannel members are placed back to back and carry the walkway plate 35on which are mounted the rail 37 that supports the carriage that raisesand transports the furnace pit covers.

The walkway plate 36 extends over the box formed by the stiffener angleplate 33 and is attached to an angle plate 38 which is secured to theupper end of the steel wall 8 and to the end of the walkway plate 36. Itis preferable to allow a clearance between the upper and lower ends ofthe angle plates 28 and the sti'fiener angle support member 33 and theangle plate 38 so that these members may breathe with the expansion andcontraction of the wall without engaging and binding against thesetransverse supports.

As shown in Fig. 2, the special shaped super duty fire clay blocks [8 to23 which support the curbing have an offset section as illustrated at 40and 4! so as to interlock the adjacent blocks relative to each other aswell as having them interlocked by the T-headed wall-tie 25. Theuppermost special shape 23 is the longest of the group and provides along seal off area for the underside of the insulating curb line brick2.

The structures as shown in Figs. 1 and 2 represent the outside or sidewall of the pit and the structure as illustrated in Fig. 3 is similar tothe structures as illustrated in Fig. l but represents the end wall ofthe pit adjacent to the recuperators. The number and names of the partsshown in Fig. 3 and their relationship with each other is the same asthe structure illustrated in Fig. 1. However, the rail girder 34 hasbeen replaced by the fabricated beam structure 43, the lower end ofwhich is supported by the angle plate 44 secured to the outer wall 8,thereby stiffening the outer wall, and is braced intermediate of itsends and adjacent the seat It by the channel member 45' which functionsas a stiifener member for supporting the wall at the seat l0 and alsofor aiding and stiffening the girder member A3.

The upper end of the girder member 43 supports the outer curb member 46which rests on. the expansion layer that is defined by the angle members48 and 49, the latter being secured to the upper end of the outer steelwall 8. This outer curb member 46 is mounted in spaced relation with thefloor member 553 which is supported by the girder 5i independent of thepit. furna e;

This floor member 50 protects the recuperator' employed to heat thegases for operating the fur-;

nac'e' which floor members 50 are ordinarily positioned intermediatepairs of pit furnaces and are used to temporarily support the pit coverwhen the same is not in position over the pit.

' The pit cover 52 is provided with a downwardly extending sand-sealingskirt 53 which seals the opening of the pit. The cover member isprovided with a series of lining clocks 54. These blocks are supportedfrom the framework as illustrated at 55 and the frame of the whole ofthe cover is supported at the four corners of the pit. Thus, there is noweight of the cover on the curbing. The furnace pit has upwardlysupporting members at the four corners of each pit that are carried fromthe foundation for the purpose of supporting the cover frame alone. Thecover is raised from the pit by the cover carriage that spans the pitand runs on the track, one rail of which is shown in Fig. 1. The coveris then traversed over the section 58 leaving the pit open to the extentrequired for removal of the-billets therein.

" Referring now to Figs; 4 and 5 which show an intermediate wall sectionof two adjacent pit chambers, pit i is illustrated on the right and pit68 illustrated on the left. The inner lining ii of silica brick has acomplementary lining in the next adjacent pit, and there is only oneback-up wall made of first quality brick which is indicated at El whichforms the back-up wall for each pit. The upper surface of the back-upwall BI is provided with the inner shelves 62, 63, and 6d.

The inner walls 5 are provided with the shelves 65, 66, 61 and 68 whichcorrespond to the shelves 12 to IE as shown in Figs. 1 and 3 and are ofthe same elevation. The air space provided above each of these shelvesis occupied by a specially shaped refractory block such as indicated at10, H, 12, I3, 14, I5, and 16 each of which match each other as theyextend upwardly along both sides of the intermediate soaking pit wall.

Each of these blocks is provided with a T- headed tie member such asindicated at 11, that are provided with spaced ears for bolting the sameon the radial flanges 18 which are positioned on and secured to eachside of the beam member 88. The beam member 80 is fabricated from theopposed channel members 8| which are spaced apart and provided with aninner box member 82 supported on angle 83.

The upper flanges of the oppositely disposed channel members 8| form theprincipal structure of the beam and are provided with a grating or walk84 that is held in place by the long flanges and the pan members 85which contain the sand for the sand seal 86 for each pit. The curbingblocks 81 are supported on the topmost special form blocks 16 and arealso tied together in the ordinary masonry way with the blocks 16 andabut against the outer flanges of the sandseal trough members 85.

As shown in Fig. 5 the special form blocks 16 have vertical anglemembers 88 and 89 which interlock with each other and aid in pulling theblock members in position. The T-headed members l! are also carried byslots 24 that are constructed in the same manner illustrated by theT-headed member in Fig. 2. It will be noted that the lowermost blocks'10 and H are secured by the wide T-headed member 90 which is bolted tothe bottom flanges of the channel members 8! as indicated in Fig. 5, andthey are not bolted to the radial plates 18 as these plates are employedto hold all of the other special block forms,

The shelves 62 to 68 inclusive also form air spaces between the top ofthe center wall and the special shaped blocks, yet, each of the spacesformed are sealed from each other and permit relative longitudinalexpansion and contraction. The curb being of a lighter masonry sectionand being supported by rigid structural members that are carried fromthe four supports at corners of the pit directly mounted on thefoundation will not vary in height. However, the heat of the large andheavy expanse of masonry formed by the pit walls, both the outer walland the intermediate wall are permitted to expand and contract and thustake up space allowed between the steps yet, there can be no leakageinto or from the furnace pit chambers to the outside or to adjacent pitfurnace chambers by reason of these closed and interlocking independentstep sections of the furnace wall.

The outer wall construction and the common wall construction aresomewhat similar to each other varying only in the manner in which theyare supported. However, the specially shaped blocks are supported andkeyed with each other in the same manner, and they are both hung fromthe steel structure rather than being hung or otherwise supported by themasonry forming the wall of the pit chamber.

I claim:

1. A furnace structure comprising a bottom, an annular wall formingfurnace chamber with said bottom, a frame extending above and on theouter side of said annular wall, an annular curb supported by said frameto extend over the top of said annular wall and in spaced relationtherewith to allow for sealed vertical expansion between the top of theannular wall and the annular curb, a roof supported independently ofsaid annular curb and forming a closure for the top of said furnacechamber, and sealing means between said roof and annular curb to isolatesaid furnace chamber as an independent pressure chamber.

2. The structure of claim 1 characterized in that said sealed verticalexpansion between the top of said annular wall and the underside of saidannular curb are formed in a series of independent steps permittingexpansion and contraction of the annular wall relative to the annularcurb.

3. The structure of claim 1 characterized in that said sealed verticalexpansion between the top of said annular wall and the underside of saidannular curb are formed in a series of independent steps permittingexpansion and contraction of the annular wall relative to the annularcurb, the steps formed between the annular wall and the annular curb arelaterally blocked off from one another to provide independent expansionchambers.

4. The structure of claim 1 characterized in that said annular curb ismade up of a series of masonry forms each supported directly from theframe independently of said annular wall.

5. The structure of claim 1 characterized in that said annular curb ismade up of a series of masonry forms each supported directly from theframe independently of said wall, adjacent ceramic forms making up theannular curb being interlocked in offset steps with one another.

6. The structure of claim 1 characterized in that said annular curbsupports an annular sand seal into which an annular sand seal skirtprojects to seal said furnace chamber.

7. The structure of claim 1 characterized in ace-aces that. said furnaceis'provided with a: plurality of chambers,- and said frame includes. atransverse beamsupported above a center wall section div-iding saidfurnace chambers.

it. The structure of claim 1 characterized in that said furnace isprovided with a plurality of chambers, saidframe includes a transversebeam supporting a center curbabove a center wall dividing said. furnacechambers; the top of said center wall and the underside of the centercurb thereover are formed in a series of independent steps permittingexpansion and contraction of the center wall relative to the centercurb.

9. The structure of claim 1 characterized in that said furnace isprovided with a plurality of chambers, said frame includes a transversebeam supporting a center curb above a center wall dividing said furnacechambers, the top of said center wall and the underside of the centercurb thereover are formed in a series of independent steps permittingexpansion and contraction of the center wall relative to the center curband the steps formed between the. center wall and the center curb areblocked, off: from, one another to,

provide, independent expansion chambere.v

10; The structure of claim 1 characterized in that said furnace isprovided with; a plurality of chambers, said frame includes a transversebeam supporting a center curb above a, center wall d-ividing saidfurnace chambers, and said center curb is made up of a series of masonryterms each supported directly from said beam independently of said wall.

11. The structure of claim 10.- characterized in that said masonry formson the; center curb are interlocked transversely of the: curb.

CARL-L.

References Cited in the,- file Of. this patent UNITED STATES PATENTSNumber Name Date 693,252 Fiske v Feb 11, 1902 925,519 Simkins June 22,19119 1,432,737 Adams i O,ct. 24,1922 2,596,180 Sherman r May 13 1952

